• Hypersonics haven't killed the warship.
    Hypersonics haven't killed the warship.
  • The Hypersonic Scramjet able to go from New York to Tokyo in 2 hours. [Jerad Kaliher via Flickr]
    The Hypersonic Scramjet able to go from New York to Tokyo in 2 hours. [Jerad Kaliher via Flickr]
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The warship is dead and hypersonic missiles are overrated.

The two halves of that sentence seem to oppose each other. After all, there’s been a lot of talk in recent months of the need to redesign Australia’s force posture to meet the rising threat from China, and much of this talk is based on the assumption that Beijing’s hypersonic missile technology is about to end the reign of warships.

Most notably, renowned strategist Hugh White has called for the government and the ADF to plan to defend Australia alone. White’s argument is based on a premise he previously argued in a 2017 Quarterly Essay, Without America: Washington will lose strategic leadership in Asia in the face of China’s growth trajectory and rising ambition.

To independently defend the continent’s sea and air approaches, White calls for Australia to raise defence spending to 3.5 per cent of GDP, increase our submarine fleet fourfold, double the number of fighter aircraft, sell the newly-built Hobart-class air warfare destroyers and the Canberra-class landing helicopter docks, cancel the contract for the Hunter-class frigates and contemplate acquiring nuclear missiles.

White’s plan aims to reduce the ADF’s dependence on large surface ships that he believes are indefensible against hypersonic missiles. White’s plan, in a nutshell, assumes that hypersonic missiles will kill the warship.

This plan has copped some criticism. Michael Shoebridge of ASPI observed that White’s argument misses the role of surface ships in protecting shipping and thus sustaining the war effort.

“Strategy is about more than fighting, it’s about shaping the environment so that war is prevented and if it has to be fought, it’s fought from the strongest position,” Shoebridge argued. “None of White’s proposed force structure seems well-placed to protect shipping and aircraft bringing what our economy would need to sustain a conflict lasting more than a couple of weeks.”

Others have put forward alternative plans, however, that also suggest hypersonic missiles are about to end the era of large surface vessels. Professor Andrew Davies of ANU has argued that “large and slow multi-billion-dollar platforms constrained to a two-dimensional surface have little future in the 21st century.”

ASPI’s Dr Malcom Davis cites the Hudson Institute: “It is the hypersonic missile capability that will keep us out of the Indo-Pacific and [will render] aircraft carriers operationally useless.” If this is true, it is safe to expect a similar effect on the usefulness of large frigates and destroyers.

But is this assumption correct? Will hypersonic missiles really end the era of warships?

The answer is no - but not only because hypersonic missiles are overrated. Hypersonics won’t kill the warship because the warship is already dead.

What are hypersonic missiles?
Hypersonic missiles are, as the name implies, missiles that are capable of reaching hypersonic velocities of at least five times the speed of sound (Mach 5).

Hypersonics fall into two broad categories; scramjets and boost glide missiles. Boost glide variants are taken to high altitudes by a rocket before they are released to glide towards the target. Their advantage lies in the fact that the rocket technology required is well-understood and less expensive than scramjets.

Scramjet missiles, on the other hand, use a booster to reach hypersonic speeds, at which point an ‘air-breathing’ engine takes over to compress incoming air before combustion with no moving parts. This propulsion mechanism could allow scramjet missiles to achieve greater ranges than boost glide variants, but developing these engines is technical and costly.

“The difference between a boost glide and a scramjet is the same as the difference between normal surface-to-air missiles and cruise missiles,” Brad Yelland, Chief Technology Officer for BAE Systems Australia, explained to ADM. “Boost glides have a large, usually solid propellant rocket motor that boosts the flight vehicle up to hypersonic speeds. The vehicle then ejects the boost motor and glides on. From the moment you eject the boost motor, you’re slowing down.

“With a scramjet, the engine sustains that speed. You’re still using a boost motor to get up to speed, but your range is now only dependent on the fuel you’ve got to burn. But scramjets are expensive, highly technical and very difficult, whereas boost glides are pretty simple.”

The physics behind hypersonic flight have been known for decades. Yet developments in material composites have only recently allowed aircraft to withstand the temperatures of hypersonic flight for useful periods of time. New power generation technologies are also enabling hypersonic missiles to stay in the air for longer.

“When you look at the physics of it, there’s no revolution,” Yelland said. “But the ability to fly for long periods of time at high speeds causes all kinds of heat and power generation problems.

“These things are glowing hot; cryogenic-type cooling is difficult if you haven’t got the ability to manufacture novel shapes with in-built cavities. 3D printing now allows us to develop cooling systems internal to the structure itself.

“Steering something going at Mach 10 also takes a lot of energy, and the technology around the generation, storage and management of electrical energy has changed.”

The next arms race
The US has pioneered much of the new research into hypersonic flight. NASA’s X-43 scramjet vehicle successfully reached Mach 9.6 in 2004 and its successor, Boeing’s X-51, flew at Mach 5.1 for roughly 210 seconds in 2013. The Pentagon’s Undersecretary for Research and Engineering, Michael Griffin, has reportedly prioritised hypersonics development above every other program.

Other countries are also putting in significant effort. Russian President Vladimir Putin has claimed that his country has two operational hypersonic missile types with a third submarine-launched variant in development. France and India are reportedly collaborating with Russia, and Japan plans to conduct hypersonic weapons tests between 2023 and 2025. Australia is contributing to US hypersonics programs, providing expertise and globally competitive guidance and control systems.

In recent years, however, China has taken the lead. Beijing has reportedly conducted 20 times as many hypersonic flights as the US and is investing heavily in hypersonic testing facilities. Chinese researchers presented more papers at a 2017 American hypersonics conference than all of the other countries put together.

In August last year, China tested a hypersonic ‘waverider’ – an aircraft capable of riding its own shockwaves – called the ‘Starry Sky 2’. It was first carried into space by a conventional rocket before separating and conducting turns, maintaining velocities above Mach 5.5 for more than six minutes and reaching Mach 6 under its own power. To top it off, the aircraft landed intact in a designated target zone. If reports of the test are accurate, it places China at the front of the hypersonics race.

“China and Russia are leading the way in this,” Yelland said. “In some ways the Western world has been caught a little off-guard. But the West has the ability to accelerate.”

A senior RAN source at a recent public event confirmed that the West, including Australia, has fallen behind China and Russia in developing and testing hypersonics.

“We [Australia] have fallen behind in hypersonics despite being a world leader in the past,” the source said. “We are actively investing in this space to get back on track."

“We’re working closely with the US, and we’ve got some world-leading guidance and control technologies here at BAE Systems Australia,” Yelland said to ADM. “We’ve shown this on previous weapon program collaborations with the US such Nulka and ESSM. We’ve certainly got the ability to contribute.”

Can hypersonic missiles be stopped?
So, will hypersonic missiles really push warships out of the Indo-Pacific? They are certainly difficult to defend against, combining immense speed with an ability to fly and manoeuvre at altitudes that are problematic for existing missile defence systems.

“If you launch a Mach 9 missile from 100 kilometres away, it will take 33 seconds to travel that distance,” Professor Andrew Davies said to ADM. “During that time a target travelling at 20 knots will move 340 metres. A Nimitz-class carrier is 317 metres long.”

Let’s try and put that in perspective: in the time it takes the average adult to read this sentence, a hypersonic missile moving at Mach 9 could travel roughly 31 kilometres (the distance between the Sydney CBD and Palm Beach, or Parliament House to Lake George). A ship moving at 20 knots could only travel the length of a rugby field.

“By the time you realize a hypersonic missile is coming your way, you’ve got less than 10 seconds to react,” Yelland said. “And if you hit anywhere on a warship with a hypersonic missile, you’ll sink that ship.”

The altitudes at which hypersonic missiles travel means existing missile defences are unlikely to offer much help. Once separated from the rocket, boost glide missiles could travel laterally across atmospheric layers before dropping towards a target. Scramjet missiles could also fly at altitudes below the typical operating range of Aegis or THAAD and above that of Patriot batteries.

On the surface, hypersonics may seem to spell the end of large warships. No defensive system currently exists that can counter manoeuvrable missiles moving laterally through the atmosphere at over five times the speed of sound. How can this technology be overrated?

But that doesn’t mean no defensive system can exist.

“Any weapon potentially has counters,” Prof Davies said. “Hypersonic weapons won’t be 100 per cent effective.

“Is the effectiveness of hypersonics substantially higher than previous weapons systems? Potentially yes, but there are still some technical problems in steering a hypersonic weapon towards a moving target.

“If something’s going really fast, it’s hard to turn. The laws of inertia don’t get turned off for hypersonic weapons. The rhetoric you see about highly manoeuvrable hypersonics – pick one or the other. You can’t have both. If you have a missile moving at Mach 9, it takes two and half seconds to move through 10 degrees, give or take. In that time, it travels 7.5 kilometres.”

According to Yelland, the question depends on the definition of manoeuvrability.

“A fighter jet has a manoeuvrability up in the high single-G figures, possibly pulling up to 12 Gs. That’s regarded as highly manoeuvrable. You could easily pull 100 Gs on a hypersonic missile,” Yelland said.

“The difference is that the speed significantly increases the radius of turn. So while you’re pulling a lot of Gs, we might be talking about a half-kilometre radius turn with a fighter jet versus a 20-kilometre radius turn with a hypersonic missile.”

 

The Hypersonic Scramjet able to go from New York to Tokyo in 2 hours. [Jerad Kaliher via Flickr]
The Hypersonic Scramjet able to go from New York to Tokyo in 2 hours. [Jerad Kaliher via Flickr]

Hypersonics are not invincible
This relative manoeuvrability problem means hypersonic missiles could be vulnerable to technologies that disrupt their in-flight course corrections.

Research has shown that a 9.5-megawatt microwave source could damage guidance systems inside a hypersonic weapon 12.5 seconds before it hits, creating a half-degree angle change that would cause the missile to land 350 metres away from the target. This technology is not flawless - missiles could be designed as a Faraday cage to reduce their vulnerability - but it is plausible.

“The other thing that needs to be considered is what guidance system the missile is using,” Yelland said. “If it’s also using some sort of radio frequency or infrared seeker then you’ve got to counter that as well.”

Some posit that direct energy weapons based on high-power laser beams might serve as an effective defensive system: but according to Yelland, hypersonics are designed to withstand the heat such systems could bring to bear.

“Hypersonics are already designed to withstand heat, so a laser directed energy weapon which relies on generating a lot of localised heat is probably not going to work,” Yelland said. “Of the directed energy weapons, RF-based ones are more likely to provide potential countermeasures, where you’re trying to upset the electronics.”

The key to defending against hypersonics may also lie earlier in their launch process, or what missile defence experts refer to as the ‘problem chain’. The first problem any missile needs to overcome is simply finding the target, meaning hypersonic missiles rely on data links that are vulnerable to cyber disruption. This concept has also been referred to as ‘left of launch’ in an integrated air missile defence (IAMD) sense; stopping the launch before it even happens.

“Anything that’s not line of sight is much harder to get an exact position on,” Prof Davies said. “Over-the-horizon radar will give a rough position but nowhere near good enough for position targeting.

“If you’re targeting a ship that’s a long way out at sea, you need line-of-sight or the ability to communicate to real-time satellite-based systems. All the data links there are vulnerabilities.”

The second problem both boost glide and scramjet hypersonic missiles must overcome is accelerating to speeds above Mach 5. This provides an opportunity to find and destroy hypersonic missiles while they’re still on the ground (or not far from it).

“There’s no doubt that if we had systems that could detect a launch and take out the missiles in the first phase of flight, that would be the way to do it,” Yelland said.

In short, whilst hypersonics are certainly going to pose a significant challenge to warships and other large high-value targets, the threat may not be as drastic as some claim.

“On balance, hypersonics are an evolution, not a revolution,” Prof Davies said. “The most revolutionary aspect could be to destabilise nuclear deterrence.”

But hypersonics couldn’t kill the warship anyway. The warship was already dead.

So who killed the warship?
To understand how the warship died, we need to zoom out – way out. Imagine you’re Chinese President Xi Jinping, sitting in your Beijing office and thinking about how to improve China’s strategic position.

First, consider your needs. You must ensure internal stability above all else, which means you need to secure enough resources to keep the economy growing. China’s history of catastrophic political implosions are a warning of what can happen if you fail.

“The legitimacy of the Communist party relies on two narratives,” Prof Davies said. “First, we’re bringing you prosperity, and second, we’re the protectors of Chinese nationalism.”

The vast majority of imports that bring prosperity to China, and thus keep the Communist Party in power and you safe in your office, pass through Southeast Asian seas before arriving at Chinese ports. You need to keep these maritime arteries open.

Now consider your vulnerabilities. The only navigable passages through these seas are controlled by a wall of US allies and military bases: Japan and South Korea in the north, Taiwan in the middle, the Philippines and Singapore in the south, all reinforced by Australia and Guam. You’re immensely vulnerable. It is as if Australia were fenced in by a string of Chinese military bases between East Timor and Vanuatu.

There is no feasible military solution to that problem. Any attempt to break through the wall by force requires a complex amphibious operation that will be attacked at sea by US and allied forces. Even if you manage to land soldiers on a foreign beach, your navy can only take around 25,000 in one trip. They’d be outnumbered several times over by defending forces.

“The Chinese could prevent the US from establishing air superiority over the Taiwan strait,” Prof Davies said to ADM. “However, whether they’d have enough control of the air and sea themselves to do anything is really debatable.”

For the sake of argument, let’s assume you manage to establish a beachhead. You’ve then got to continuously transport enough troops across contested waters to outpace enemy reinforcement rates whilst fighting the world’s largest and most technologically advanced navy and a suite of its allies. Remember, none of your military leaders or personnel have any combat experience – something the Chinese leadership refers to as the ‘peace disease’.

Sure, you’ve got enough missiles to restrict American surface ships’ access to the South China Sea and slow their reinforcement rates. According to Professor Davies, you could also roll out enough mines in the Taiwan Strait overnight to prevent American submarine access. Your new hypersonic weapons and other long-range strike capabilities could hit US regional military bases, and your lower-cost dispersed force model could do some real damage. You certainly won’t give Washington an easy victory.

“Numbers have a quality of their own,” Prof Davies said. “The Americans would have some really rude awakenings in terms of what dispersed, low capability anti-submarine warfare forces can do.”

Nonetheless, you can’t fully prevent allied submarines, land forces and aircraft from enforcing a distant blockade of global shipping lanes and effectively choking you out of a fight over time. You’d also face the challenges of occupying and defending the land you’ve just seized against local resistance and a potential counter-invasion.

“People talk about the access problems we’d have in the waters around China,” Prof Davies said. “But China’s got an access problem to the rest of the world. The Chinese know that.”

Strategically speaking, you’ve also just shot yourself in the foot: the arteries of trade you went to war to secure must now pass through a hemispheric war zone in the Western Pacific. The US, on the other hand, can trade comparatively unmolested. That means time is now on your opponents’ side, which is problematic given you’re the occupying force. Any attempt to take on the US or its allies by force also risks nuclear annihilation – particularly if you use hypersonic missiles.

Of course, there’s always a possibility that war could break out through a sequence of events outside your control. It pays to be prepared, and part of that preparation involves keeping ahead of the curve and investing in hypersonics. Yet for all China’s military investments, RAND forecasts show that it remains highly likely to lose a war with the US of any length or severity, and it makes little sense to risk internal collapse by initiating a war that you’d eventually lose.

Friction killed the warship
So, you can’t break down the wall by force. What are your other options? What strengths can you leverage to reduce your vulnerability?

Let’s return to the prediction underpinning Hugh White’s argument: China’s demographic and economic growth trajectory will erode US primacy in Asia. This prediction also underpins the arguments of many of White’s critics and those offering alternative post-America strategies for Australia. Although China faces plenty of its own challenges, including economic deceleration and a demographic bubble, let’s assume it is accurate.

Erosion is a product of time and friction. China’s autocratic political system grants its leadership a greater time horizon than US presidents constrained by electoral cycles. An alternative course of action, therefore, is to apply friction and wait for the wall to erode, like waves beating against the rocks.

Of course, it is always possible that Beijing’s hand could be forced, particularly by a declaration of independence from Taiwan. Yet the sheer risks and costs involved means war is unlikely to be Beijing’s preferred course of action.

“There are limits to China’s patience,” Prof Davies said. “Hong Kong is starting to show that now. If one of the pillars of Communist legitimacy falls over, there’s always the danger that they will resort to the other. I don’t think you can rule out sleepwalking into a stupid war.”

If we assume Beijing can avoid sleepwalking into war, the two basic options available to Chinese leaders looking to secure the country’s future are to try and break US primacy in Asia by force, or apply friction and wait for economics and demographics to do the rest. The first option is costly and almost certain to end in failure. The second is already happening.
Hypersonics won’t kill the warship. Friction already has.

The enemy has voted
Warships died when nuclear deterrence forced revisionist states like China to achieve their foreign policy goals short of open war with a peer competitor. Hence why the US Navy has only sunk one major surface combatant in the last seven decades. The RAN has neither sunk nor lost a vessel in battle since WWII. That is the edge of living memory.

This is not to say that vessels sunk or lost is a measure of warships’ value. As many readers will point out, warships remain useful for transporting military and humanitarian supplies, conducting anti-piracy patrols, border protection operations and sanctions enforcement, engaging in naval diplomacy, and from time to time, ship-to-shore bombardments against non-peer adversaries.

It is to say that in the context of crafting a force posture to guard against a nuclear-armed peer competitor like China, warships are already dead. They are a right of boom tool confronting a left of boom problem.

As Professor Davies argues: “Large and slow multi-billion-dollar platforms constrained to a two-dimensional surface have little future. In fact, I think we passed that point decades ago but nobody noticed because there hasn’t been a large-scale maritime conflict between near-peers since 1945.”

Left of boom friction – conflict fought below a threshold of violence that calls for the use of hypersonic missiles and warships – has already redrawn the strategic map of Asia. China has used a maritime militia of fishermen and oil rigs backed by lightly armed cutters to seize reefs and islands throughout the South China Sea, which it has subsequently fortified with precision missiles to erode US naval primacy in the Western Pacific.

Beijing has also used media operations to influence foreign news coverage of these occupations, used ‘lawfare’ to challenge international legal norms and jurisdictions, sent scientific research ships to conduct reconnaissance of seabed lines of communication, applied targeted economic pressure to force other states to withdraw military forces, and deterred military intervention with diplomatic and cyber threats. It is now expanding these methods to the South Pacific. What help were our warships?

Some might argue that warships remain valuable in other ways. How else can a navy conduct anti-submarine warfare, protect sea lines of communication or enforce distant blockades?

But these tasks are not the exclusive domain of large warships. As Professor Davies notes, China’s ‘civilian’ maritime militia is already capable of keeping US submarines out of the Taiwan Strait. It is easy to imagine this ‘fishing fleet’ using data gathered from an extensive seabed sensor network and autonomous undersea gliders to detect and track submarines, which could then be targeted by unmarked and unmanned platforms. The same militia could also enforce a left of boom blockade similar to the one Russia is currently enforcing in the Sea of Azov against Ukraine.

In any case, warships are already unable to protect our sea lines of communication from Chinese ‘research vessels’, which are mapping seabed internet cables and deploying robots that could tap or sever them in a conflict. They have also been demonstrably unable to stop China seizing reefs and islands by left of boom means to then expand its precision missile capabilities and threaten almost all sea lines of communication and supply in the Western Pacific. Warships have been helpless against their own demise.

The question to answer is this: why would China move right of boom tomorrow for results it is achieving left of boom today, particularly given the near certainty of defeat? And if warships cannot defend us against left of boom operations today, what use will they be tomorrow?

How do we defend Australia today?
The arguments of White, Shoebridge, Davis and others may take different perspectives on how to best defend Australia tomorrow, but few address how we defend Australia now. To paraphrase John Lennon, strategic erosion is happening while we’re busy making other plans.

Even if the economic and political will were mustered to raise defence spending to 3.5 per cent of GDP, quadruple the submarine fleet, forward position military forces and buy new warships, we would remain unable to prevent China from using left of boom tactics to keep punching holes in Australia’s force structure. The Commander of US Indo-Pacific Command Admiral Philip Davidson has told Congress that Beijing’s left of boom conquests have already effectively pushed the US Navy out of the South China Sea. This has happened without hypersonic missiles and despite the presence of US warships.

Let’s sum up. Australia’s new fleet of warships will provide theatre air defence, modern anti-submarine warfare capabilities and a suite of amphibious options. Hypersonic weapons will threaten those warships with an unprecedented combination of speed and manoeuvrability. Newer technologies may mitigate the hypersonic threat. But what can any of these do against the left of boom friction happening while you read this article?

So is the hypersonic threat to warships really the problem? Or do we need to start asking different questions?

This article first appeared in the October 2019 edition of ADM.

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